Xylooligosaccharide increases bifidobacteria but not lactobacilli demonstrating potential for obesity prevention and treatment (37.6)

Abstract

Background: Prebiotics can alter gut bacteria in obese subjects towards patterns seen in lean individuals.Objective: This study was conducted to determine the tolerance and effects of xylooligosaccharide (XOS) on human colonic microbiota, pH and short chain fatty acids (SCFA).Design: Healthy adult subjects (n=32) were randomized to receive 1.4 g, 2.8 g XOS or placebo in a 12 week study consisted of a 2‐week run‐in, an 8‐week intervention,and a 2‐week washout. Stool samples were collected at baseline, after 4 and 8 weeks of intervention and 2 weeks after the intervention for culture, pyrosequencing of community DNA, pH and SCFA analyses.Results: XOS was tolerated without significant gastrointestinal side effects. Both XOS groups achieved increases in Bifidobacterium counts compared to the placebo subjects, with the 2.8 g/day group showing significantly greater increases than the 1.4g/day group. Total anaerobic counts and Bacteroides fragilis group counts were significantly higher in the 2.8 g/day XOS group. There were no significant differences in the counts of Lactobacillus, Enterobacteriaceae and Clostridium between the three groups.XOS had no significant effect on stool pH, SCFA or lactic acid. Pyrosequencing showed no notable shifts in bacterial diversity.Conclusions: XOS supplementation may be beneficial to gastrointestinal microbiota and 2.8 g/day may be more effective than 1.4 g/day.